# Julia 1.9.alpha1 multi thread

**URL:** <https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526>\
**Category:** General Usage\
**Created:** [November 20, 2022, 6:30am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526 "2022-11-20T06:30:35Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![Mr.Benz](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mr.benz/32/44494_2.png) [@Mr.Benz](https://discourse.julialang.org/u/Mr.Benz)\
**Post date:** [November 20, 2022, 6:30am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/1 "2022-11-20T06:30:35Z")

</div>

I have installed julia 1.8.3 and julia 1.9.0 alpha1.  
when enter julia -t auto command ,julia 1.8.3 is running.  
how to start julia 1.9.alpha1 with mulit threads.  
Also,Julia 1.9.alpha1 is not supporting vs code with jupyter notebook.

Please tell me how to solve it.

Thank you

---

<div class="post-metadata">

**Author:** ![ufechner7](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ufechner7/32/51363_2.png) [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Post date:** [November 20, 2022, 6:40am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/2 "2022-11-20T06:40:55Z")

</div>

Well, if you want to try different Julia versions use [GitHub - johnnychen94/jill.py: A cross-platform installer for the Julia programming language](https://github.com/johnnychen94/jill.py)

```julia
pip install jill
jill install 1.8
jill install 1.9 --unstable

```

You can then switch the active version with:

```julia
jill switch 1.8

```

or

```julia
jill switch 1.9

```

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [November 20, 2022, 7:37am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/3 "2022-11-20T07:37:07Z")

</div>

Typing `julia` in your terminal will start the first program called `julia` found on your PATH. If you want to start a different executable with the same name you either have to give the full path to the executable you want to start, or navigate to the folder it’s in and do `./julia` or create a symlink (on Linux, or whatever the equivalent is on Windows/MacOS) to disambiguate versions (eg I have a series of `julia1x` symlinks to start different Julia versions).

---

<div class="post-metadata">

**Author:** ![Krastanov](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/krastanov/32/6817_2.png) [@Krastanov](https://discourse.julialang.org/u/Krastanov)\
**Post date:** [November 20, 2022, 8:30am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/4 "2022-11-20T08:30:33Z")

</div>

As @nilshg already described, if you have multiple versions of julia installed, you need a way to disambiguate which one is being used by various softwares.

As already mentioned, what starts when you run julia from the terminal depends on the PATH variable in your current terminal session. Or you can simply use the full path to the julia binary in its installation folder.

For jupyter, which julia is started depends on how you installed jupyter/ijulia. You can either look up IJulia’s documentation on how to register a new “jupyter kernel” (probably a single easy configuration function to be called from the julia repl) or you can manually edit your current one or make a new one (my preferred way of doing it as it provides more flexibility). To do it manually, look up the kernel configuration files you already have in `~/.local/share/jupyter/kernels`.

For vscode, similarly, you need to tell it which julia executable you want it to use. It is in the configuration page of the vscode julia plugin.

As @ufechner7 mentioned, there are more automated ways to switch between versions. There are tools that let you install multiple versions of julia and swap between them freely, without having to edit configurations in your other pieces of software. That is done by having one single “file” called `julia` reachable from your PATH variable, but the version management software changes what that file points to. @ufechner7 likes `jill`, which depends on python. The python dependency is very inconvenient for me, so I prefer the much more self-sufficient [`juliaup`](https://github.com/JuliaLang/juliaup#installation), which has its own pros and cons.

---

<div class="post-metadata">

**Author:** ![Mr.Benz](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mr.benz/32/44494_2.png) [@Mr.Benz](https://discourse.julialang.org/u/Mr.Benz)\
**Post date:** [November 20, 2022, 8:48am UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/5 "2022-11-20T08:48:57Z")

</div>

> [@Krastanov](#):
>
> @ufechner7

Thank you. it solved my problem

---

<div class="post-metadata">

**Author:** ![jbytecode](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jbytecode/32/17719_2.png) [@jbytecode](https://discourse.julialang.org/u/jbytecode)\
**Post date:** [November 20, 2022, 3:00pm UTC](https://discourse.julialang.org/t/julia-1-9-alpha1-multi-thread/90526/6 "2022-11-20T15:00:16Z")

</div>

A short note for Jupyter notebooks, they’re still problematic in 1.9, follow the issue: [Regression affecting IJulia · Issue #47196 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/issues/47196)